I have started to code up a proof of concept 16 channel JACK audio mixer and associated Zynthian integration. You can follow progress on the zynmixer branch. So far I have created the 16 stereo input channel, 1 stereo output channel (32:2) mixer with level and pan (actually balance) control for each channel and created a UI screen with 16 faders. The UI is only touch / mouse controlled at the moment and only controls the levels, not balance. The mixer is not integrated with Zynthian audio routing (something I may ask for help from a grown-up). It is very much a work-in-progress and there are many features I intend to borrow from other projects I have done in a similar ilk so expect rapid improvement.
If nothing else this is an escape from the grind of continual step sequencer development and yet another reason for @wyleu to threaten me with his torture dungeon.
I expect to have level and balance working soon with relative touch control (as opposed to current implementation which is absolute), channel legends, fader backgrounds, master faders, etc. I guess mute / solo might be nice and may even consider routing channels to peak meter (or, if not too much overhead, individual level metering…).
I wouldn’t look at this if you are even slightly snowflake as it doesn’t do much yet and may offend your sensibilities!!! I thought I should mention that I have done the work though in case you were all busy beavering away in your man-caves on similar solutions. (@wyleu probably has a magnet on a pendulum driving his auto-pan…)